England's road agency will spend around £58m over four years on digital cameras, primarily to monitor variable speed limits.
The cameras ordered may also be used to measure average speeds, as well as monitor hard shoulder running, closed lanes and temporary speed enforcement.
Equipment will have to undergo "extensive …

COMMENTS

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Speed limits

I still think that reducing posted speed limits by 1mph would be more cost effective than this without particularly affecting travel times. For the same reason that advertisers usually take a penny off the price, (29) gets you thinking 20-something, (30) gets you thinking 30-something.

More big brother...

I wonder how long it will be before this new systems is good enough to be able to work out your mileage, MPH, which roads you used and how much Road Tax we can charge you for driving at stupid times:

like the time you start work,

or the time the kids need to be at school

Or the time you finish work

or the time you pick up the kids from school

Just another way to screw people with jobs and responsibilities out even more of their hard earned money. Of course by the time it comes in we will have all lost our jobs and won't have to worry about it.

DOH!!! Sorry its not for that is its to improve road safety. Ahh I see. Just like the extortionate rates charged at Airports is to combat terrorists.The fact that we make loads of money out of it is just a pleasent side effect.

HA short of cash is it?

(untitled)

Yeah right. If the variable limit was only used to minimise congestion it would only be in use at times when traffic volume is high enough to cause congestion. Is that what is observed? No. Instead they get switched on at 06:30 every day even when there's sod all on the road. Why? So that they can switch on the speed cameras and start the tax rolling in.

And do they help with congestion? Grudgingly I have to admit they do at times of high traffic volumes. OTOH they cause a hell of a lot of congestion when traffic volumes are low. 4 lanes moving at varying speeds smoothly are reduced to 4 lanes queueing up to get past some bell end who slows to 56* in lane 3 as soon as the variable congestion creators light up.

*60 on his speedo which he assumes to be 100% accurate thus giving him the right to sit in whatever lane he chooses. Wrong on every level asswit.

AC because it's safer to stay in lane 1 with 200-300 yards of clear road in front when passing said asswit rather than shoehorn into the bumper to bumper line of repmobiles and vans in lane 4.

Ridiculous

Why not spend the money on more police? Surely the major cause of motorway accidents is people driving too close, not too fast? Get people driving more safely, and the speed becomes almost negligibly relevant, doesn't it?

Not again

Morons

Britain's roads are now more dangerous than Spain's (according to the latest figures reported in MAG's "The Road" magazine; the most recent figures I can fine on-line are from 2005 and thus out-of-date).

The obsession with speed is simply to pour money in the Exchequer's coffers; it is a pure revenue raising scheme and has NOTHING to do with road safety. If they brought back traffic policing (totally destroyed under Labour) and tackled drink/drug drivers, unlicensed/uninsured drivers, tailgaters, lane hoggers and other dangerous drivers, never mind the dangerous vehicles; if they took the BILLIONS raised through fuel duty and spent that on fixing the pot holes, poor road surface, poor signage, lethal barriers and so on; then that would be about safety.

Also, they could fund free eye tests (like in Scotland) and then demand that drivers show a valid eye test every 2 years. Not only would that will save lives, it would save people's sight.

But saving a life does not make money, only printing tickets and demanding money with menaces does that. It sounds good to the unthinking, hand-wringing, middle-class morons who fear for dear Tarquin's life as they drive their 4x4 to the school gates to keep the cherub "safe from all the cars". And keeping these morons placated is the point - it keeps the gravy train flowing.

Do you drive your kid to school? Then you are part of the problem. Why not park a few streets away (where parking will be easier anyway) and then *WALK* the child the last few blocks; hmm? Teach them how to cross the road, how to use the crossing lights etc. DO NOT ram the roads around the school and increase the danger to your child's life by relying on other drivers seeing your brainless actions (like stopping in the middle of a crossroad to let the kids out!) Or is 5 minutes out of your day not worth your child's life?

(I make little apology for the emotional blackmail at the end. I live beside a school and have to ride past it every morning; there really are parents out there who are determined to kill their children in the name of safety; it's depressing).

So...

And as for capacity...

...if Labour stopped pissing about with the trains, electrified the lines and kicked the arse of the incompetent train companies; the perhaps people would get out of their cars. Too busy taking back-handers and getting cushy directorships though.

Look at the services in France, Spain, Germany and Switzerland if you want an idea of how it should be done. Cheap(ish), reliable and fast.

Heck, decent trains would also remove the need for airport expansion by doing away with most domestic flights!

(untitled)

Hmm

Has anyone tried the M42 at non congested times?

Seems like they never turn of the variable speed limits. I went down it a couple of Sundays back, the F****** speed limit was set to 50 mph the whole way, there were no cars in the fast lane, a few in the middle lane and some lorries in the slow lane. No roadworks either, so no need for it to be a 50 zone. I think they just do it to make money.

Average Speed Camera's

We have some of these put in for some roadworks near Team Valley, A1 Western Bypass. The yellow posts etc look very permanent and it wouldn't surprise me one but if they stayed once the roadworks have gone...

Anyway - the longer I think of it the more I am steaming - FFS - I thought we were supposed to be having spending cuts. Its been proven time and time again that traffic police are a greater deterrent to a f**king camera.

Surprise... Surprise...

Hehe... Why I am not surprised...

Variable speed limit gantries have been springing up on other stretches of the M25, not just Heathrow recently as well as quite a few other places.

Theoretically, it is one of the few forms of congestion management that actually works with the other being red lights and "one car at a time" filtering-in on sliproads. It is also the only safe means to allow usage of the breakdown lane for traffic. If the motorway is running at 30mph it is pretty safe to use the extra capacity.

Unfortunately it is more likely to be used as a cash cow to issue tickets to people speeding on empty motorways out of hours than as a congestion management tool.

They want cuts?

driving ...

More cars and more cameras please.

When I am president I am going to put up many more cameras, and do nothing to ease congestion. All of you who want to use your cars can just put up with it. All motorways will be toll roads, but a concession is that the road fund license will be axed.

Anyone who wants to run a public service transport operation such as a coach or bus route, as well as taxis - will be forced to convert to greener fuels or have their licence revoked. This hopefully will bring in newer operators and provide better competition.

Anyone who can work from home WILL work from home and companies will be fined heavily if they do not proactively offer home-working as an option.

Trains will be be run as a public service again instead as "for profit" organisations but will be operated and managed by a European organisation, as they seem to do trains much better than us here in the good old UK.

Safest roads in europe...

... so I assume the highways agency won't be happy until every single person in the uk is paying stealth tax. Its an unfortunate fact of life that there are a small minority of awful and dangerous drivers but no amount of attacking the general population will EVER remove them from our roads. Personally I'd like to see driving bans for people manoeuvering without indicating, travelling dangeriously close and racing on the public highway (and as a biker, i've never felt my life endangered by someone travelling a small amount over the speed limit)

That said, if the cameras were actually used to improve traffic flow, i'd approve, but that won't pay for MPs expenses...

wanted: diplomatic number plates.

tail gate cameras?

I hope that these will include "tail gate" cameras. I don't really care if the person behind me wants to go faster, but it really isn't safe sitting only a couple of inches from my bumper in an attempt to "encourage" me to get out of his way.

If I'm overtaking a slower vehicle I'll do it at a speed that I think is safe and I'm not about to speed just because the person behind me is impatient.

Its getting silly now...

Driving on todays busy roads is bad enough, but it is starting to get stupid. 20,30,40,50,60 & 70 limits, changing limits, road layouts that change from hour to hour. Roads filld with signs telling you this that and the other... Arrg. Its starting to get so that you are looking at signs rather than the road for fear of missing something. To often people cut me up because they don't see me. Probably because of infomation overload.

If it was up to me I would ban all speed limits except 30 in built up areas, 70 on motorways and dule carrage ways, 60 everywhere else, unless the area met very strict rules then it can be 40. Nothing else.

Speed humps would be gone as would other traffic controls and speed camaras. Nothing other than lines and arrows would be alowed on the road (Those painted boxes and speed on the roads can be lethal in the wet too a motorbike).

Money well spent hey...

So money is being cut from schools and the NHS but yet they still have money to spend on this! What the hell is the gov doing...I can see the PM of the future being quoted "Hey our country maybe getting more and more stupid and sick but at least our motorways run smoothly!"

great

Speed cameras are a good tool to get stupid people to comply with the law about speeding, and it raises a profit, and it's fun!

Hope these new speed cameras are not in those too-obvious orange boxes but well-concealed. No need to induce "OMG PANIC I'm too fast" sudden brake maneuvers which make roads less safe and fail to collect the fine because people aren't speeding any more when they pass the sensor.

This countrys roads are a joke.

Seriously, having just come back from a couple of weeks driving on the continent I can give an informed opinion that the UK's roads, driving regulations, and in many cases driving attitudes are a f'in joke.

FAO UK Gov - get with the program and apply some common sense:

Change the 70 to an 80 (in dry conditions).

Change the 30 to a 20.

Only allow speed cameras around schools and through roadwords.

More traffic cops with higher 'on the spot' automatic fines for tailgaters, lane hoggers, and people driving like a tit.

Did they forget to mention a few camera types?

Like the one which records dull-eyed gimmers pulling out of junctions into oncoming traffic; or the one which records taxis parked in cycle lanes; or the one which records driving-while-stupid offenders.

Oh the joys

@The BigYin

Don't confuse "TGV" wth "French trains". Outside of that heavily-subsidised PR exercise, most French trains make the old Network Southeast look good. And they're only cheap becasue of massive subsidies from the non-train-using public.

@debaser: Agree with most of it, except for the prison sentences. Why should we pay to lock the plonkers up. Just crush whatever car they were in at the time. If it wasn't their car let the owner sue them.

One other thing. There's an easy way to deal with congestion. BUILD MORE F%^&ING ROAD. Despite what the treehuggers would have you believe the whole of the UK motorway network covers only about 140 square km, about 0.05% of the total UK land area.

"allowing more capacity"?!?!

Simple maths for politicians. Let's say we have one lane, and 50m between cars (which is actually pretty good on a busy motorway). 50m at 70mph equals 1.6s. So over the course of an hour we can put a maximum of 2252 vehicles down that lane if they're doing 70mph. Now let's say we have the same distance between cars and we're driving at 80mph. 50m at 80mph equals 1.4s. So over the course of an hour we can put a maximum of 2574 vehicles down that line. By similar working, we can only do 1930 vehicles at 60mph.

So in this example, if we could keep the lorries (typically doing 60mph) out of the way of the cars (typically doing 80mph), we can get a 33% increase in the number of cars going through. That leads to one simple conclusion - ban lorries overtaking, and you'll get better road links.

There's another reason too, which is that the biggest cause of accidents is having to rapidly respond to changes in speed of othe traffic, and the biggest cause of these changes of speed is dealing with overtaking lorries. Sure, it's the driver's fault that they can't react, but it's the lorry driver's fault that he's pulling out into a stream of fast-approaching traffic. In other words, if you ban lorries overtaking, you'll also reduce your accident rate practically to zero overnight.

So forget speed cameras. If no lorry is allowed to overtake anyone or anything, ever, then we'll have safer, faster roads. Job done.

Wasteful

I find this as another example in the many, that have reared their ugly head this year of politicians and ministers being completely out of touch with the reality.

All that has been heard over the summer break is talk of 'cuts' in public spending, which will at some point lead to some people losing their jobs in certain areas of public services and less if nil recruitment in other areas of public service, yet this barmy prime minister is allowing £100 million to be frivolously spent on watching motorists, when he ought to be concentrating on how not to be remembered as the worst prime minister this country has ever had.

Arrrgh!!!

There are a few things wrong with this country road-wise:

1. There is a general problem with too many people on the roads during peak times one solution would be to change the chelsea tractor drivers have to get their spawn to school.... if they go before the rush, this dilutes the effect. (it's their choice to have spawned little copies of themselves... not the other drivers, so why should it impact them adversely... same applies for public transport)

2: realistic speed limits on roads... there is an increasing trend in dropping speed limits on a road just because some idiot decides to take his/herself out of the genepool by driving too fast... it's evolution for frick's sake! If the dumbasses kill themselves, then over a number of generations we will get better drivers. I also have a sneaking suspicion that if councils drop a speed-limit that they don't have to maintain a road to the same level... there was a really nice national road near me, that went to 60, then 50, then 40 over the space of about 5 years, also at the same time the road quality has got considerably worse!

3: No upper limit on motorways, but active police patrols to weed out dangerous driving (undertaking, not pulling over to let faster traffic through, tail-gating) and the use of tailgating cameras (not speed cameras) to weed out some of the aggressive driving. The distance on the tailgate cameras could also be used to enforce braking distances in wet weather (with appropriate warning signage).

4: Engineering roads for safety does NOT mean slowing them down. If there's a danger of kids running out in the road (besides the evolutionary pressure this would add), add railings and/or crossings, and on faster roads, possibly a central reservation with guide rails so if people are intent on killing themselves that they don't take out too many innocent casualties.

If a road is too narrow, compulsory purchase the land either side and make it wider... I'm not a fan of this nimbyism regarding maintaining our archaic transport infrastructure because we're too afraid to use a bulldozer... (same goes for train-lines... we need to invest properly and actually do stuff knowing we WILL upset someone, it's inevitable...).

5: Remove all speed cameras and instead allow active police patrols, this would also mean no camera vans.

Speed is not a bad thing... however inappropriate speed coupled with bad driving is, this is something a camera will never be able to differentiate (yet)....

/rant.... (posted A/C as it's a blatant rant and a vent on my part...)

@graham

Hold on a Minute...

@TheBigYin...

You ask why uninsured drivers are not tackled. Well, the easiest way to do this would be to put an ANPR (Automatic Numberplate Recognition) camera on every street. Then the police would easily be able to spot untaxed / uninsured cars and act accordingly.

Something tells me you would not be happy about this either.

There's a lot of rage on here this afternoon, but it would be good if people managed a consistent argument. If there were more police on the road surely they would still be stopping people for speeding?

Don't forget that these cameras are going to be a lot more sophisticated than a radar triggered film camera (i.e. a gatso). I don't see why the ANPR network couldn't be used to deal with tailgaters as well. CCTV systems can already judge distances and movement, why not apply that technology here?

So with two of your pets hates addressed, surely what you want is MORE cameras?

ANPR cameras are of course are already used in unmarked police traffic cars -one camera on the front, one on the back to instantly (well, quickly) read every number plate that drives past the car and check for outstanding issues on the car - everything from not being on the MID or being registered to an unlicensed driver. It notifies the officers in the car if it spots one and they go and stop the car. Untaxed cars can already be removed at the roadside by police and then recovered by the owner (once the tax / insurance has been paid) or be crushed two weeks later if they don't.*

Before getting too worked up can we decide what we are worked up about? Either it's a fascist surveillance state or we let these reckless drivers get off scot free... I'm not sure we can have both...

Overtaking kills, so increase speed limits

You cannot overtake a car doing 70mph by doing 70mph, you are not supposed to be in the overtaking lanes unless you are overtaking. All vehicles can do 70mph now and they cannot fit all the vehicles into the left lane because there isn't the capacity. So two lanes of cars must be speeding, hence 80% of people speed BECAUSE THEY HAVE TO. Cut them some slack you micromanaging assholes.

Research in Texas showed that their increase in motorway speed limits from 55 mph to 75mph had NO effect on fatalities. It is not as clearcut as you think it is.

http://www.livescience.com/strangenews/050622_highway_safety.html

This study "Speed variance, enforcement, and the optimal speed limit Economics Letters, Volume 42, Issues 2-3, 1993, Pages 237-243 ",showed you get fewer accidents by harmonizing the speed of vehicles, and RAISING the speed limit was found to create smoother traffic flows than lowering them. (Can't link to it it's on Elsevier).

i.e. the risk of accidents occurs from slow vehicles mixing with fast vehicles, .... well duh, if every car travelled at the same speed in the same direction they could not hit! So putting cyclists and cars on the same roads is bad because there is a wide variance in speed. Bunching cars up in some sections is bad because where they bunch is a collision risk, and any phantom traffic jam that the bunching causes, also a collision risk before the road works.

30mph is not a magic safe number, that number came from misinterpreting a graph of the RATIO of fatal pedestrian-car crashes to all pedestrian-car crashes. In reality there was a huge *increase* of *non* fatal accidents below 30mph, which made the *ratio* of fatal to non fatal drop dramatically at 30mph, when in reality it does not. So the belief that dropping the speed to 30mph would magically make road works safe is not true*.

i.e. this graph is the one they use, but it misrepresents the data it was calculated from.

* If you're still not convinced, suppose there are 1000 accidents per million journeys that are non fatal and almost all are below 30 mph. i.e. faster roads like motorways are safer, but there are far more accidents on slower roads where pedestrians meet cars and these are nearly always non fatal.

Now suppose there is 1 fatality per million trips. And imagine if speed made NO DIFFERENCE at all. Whether 10mph or 1000mph, for this thought experiment, it's only 1 fatality per million trips.

Now calculate the same ratio Pasanen did for his graph. Notice that at 30mph there is a huge swing from fatal to non fatal accidents!.. So speed above 30 causes fatal accidents? But that cannot be, as I said 'imagine if speed had no effect on fatality' and we constructed the original data so that speed had no effect on fatality! Yet the derived graph shows speed has an effect on fatality!

So you see the problem with what Pasanen did, and nobody has checked that graph since to recognise the problem. They just quote and requote it in its different forms.

But the fix is better segregation of traffic from people and smoother traffic flows, and sometimes smoother may mean faster!

title

I've only been on the M25 once (being a northerner like) so could someone explain to me how the variable speed changes work?

I only saw one change and it was right (literally 20 meters) in front of me I obviously didn't slam on my brakes so I was technically speeding when I went past the camera... Haven't had a letter through the post though so am I just lucky or is there more than the usual 10% allowed?

We know where you are and were...

BigYin has pretty much hit it on the head. I agree that the variable limits do work to a degree, but mostly the cameras will inevitably be used to generate revenue. And probably to track where we all are (cue the paranoia!)

I also agree the motorway limit should be upped to 80 (but more strictly enforced) and that lorries should be banned from overtaking, but reducing urban limits to 20 is senseless. It's actually quite difficult to maintain only 20mph and uses more fuel because most people will be in second gear which is very inefficient. Stick to 30 except for short zones around schools etc (Sweden does this and very successfully too) and punish bad drivers: Failing to stop at a zebra crossing? 6 points and £250. Driving whilst using a mobile? 6 points and £250 etc etc etc.

And for gods sake, employ proper traffic cops again who can catch this sort oft hing and deal with it properly!!

@DaKid

>> Why not spend the money on more police? Surely the major cause of motorway accidents is people driving too close, not too fast? Get people driving more safely, and the speed becomes almost negligibly relevant, doesn't it?

More police in cars? That's supposed to make the road safer? All of the most STUPID driving incidents I have seen on the roads in in recent years have been police cars - often without their lights and sirens on. Driving at high speed around a blind bend on the wrong side of the road down a hill was one of my favourites - couple of weeks later there were two seperate pol. accs. on the same day, in the semi-rural area that I live.

Just last night I was on the M25 travelling at 70* in the lane 1, when a Police 4x4 shot past me, travelling at 90-100 - without any blue lights or sirens. It wouldn't have been so bad if he hadn't proceeded to hover six inches away from the rear of a vehicle in the third lane. Admittedly the vehicle in third lane was lane hogging a little - however whilst lane hogging is annoying and inconvenient, it isn't directly dangerous - whereas tailgating is immensly dangerous and can quickly turn a small mechanical failure or driver error into a multi car pile up with fatalities. I'm sure the driver in the tailgated vehicle would have been happy to move over much sooner, probably without the police car needing to slow down - all he needed to do was turn his flashing lights on.

*admiittedly according to my speedo, which if my sat. nav. is to be believed, is probably about 10% out (then again it was pretty close to correct when I was snapped by camera a few years ago).

I feel victimised

It was one of those accidents where there was enough blame going around for everyone involved. The layby was the bit of old road left when a corner was smoothed off. The lorry was doing a U-turn at night to get into the layby, and sticking out half-way across the road. I should have seen the lorry, but there was glare from the lights of oncoming traffic and the gentle curve of the road was pointing my lights in the wrong direction.

I was never even told if the lorry driver had been considered for prosecution. I was told I had been. It all felt very one-sided.

And the accidents which don't happen, because somebody manages to stop in time, don't get into the statistics. It's just me.

I've heard similar stories of silence from other drivers. Something happens, it isn't clearly one driver's fault, but somehow the impression arises that the other driver gets away with their stupidity. And, frankly, I see a lot of stupidity which has nothing to do with speed limits.

When was the last time you saw a truck on an ordinary road, sticking to the speed limit?

@Steve Pettifer

In Scandinavia (Might be Finland) they don't fine you a fixed amount, but a proportion of your income. There was some CEO who got fined thousands for effectively doing 40 in a 30....

I think i quite like the idea of that - not least because the last ticket i saw a policeman writing was for my ex-boss who had been caught on the phone in his Bentley. The cops even did us all a favour by writing the ticket in the car park in front of the entire office....

@Graham Bartlett

Where I live there are a number of motorways with long 2 lane stretches (M2, M26, etc), so I am well acquainted with this problem. The worst thing about lorries overtaking is that it barely qualifies as overtaking. Both vehicles will often have speed limiters fitted, and they difference in the speed is virtually non-existant. I'm not sure what the exact difference is, but it will often take one lorry about 3 minutes to over take the other, estimating (generously) the distance needed to overtake as being 20m - the difference in speed is approximately (20m/180s = 0.11111 m/s) 0.25 mph. Over a 1000 mile (almost 17 hour) journey, they are gaining less than 5 minutes - assuming that every time they come across a slower vehicle, they over take it.

I have been stuck in a queue of traffic behind two lorries on a two lane motorway, where the moment one had completed overtaking the other, the other then proceeded to overtake first - for the entire length of the motorway.

I have no problem with lorries, or anybody else, overtaking when it is sensible to do so - but no one should over take unless they can manage to travel at (say) 2 mph faster than the vehicle they are overtaking. This is probably my biggest pet peave after tailgating and poor lane discipline.

BTW, does any one else regularly travel between junction 7 and 8 (or maybe as far as 9) of the M25 clockwise. It is a four lane section,with a large separation between the two carriages for a lot of the length. Almost without fail, every time I pass through there (weekly), for fourth lane will be nose to tail traffic travelling at 65 mph, whilst (generally) the other three lanes will be virtually empty. Or how about between 14 and 15 - lanes 2, 3, 4 and 6 will be full of cars travelling at 55 - 60 whilst cars in lanes 1 and 2 are full of cars joining from Heathrow travelling at 70-80 (or more) making it very difficult to to move across into lane one to take the M4 west bound. This has to be the most poorly designed 'slip road' on the UK motorway network.

Whilst I am ranting, something they could do that would massively increase throughput on the M25 would be to make the Dartford Crossing free. Yes they would lose money on tolls, but if people didn't have to queue to pay, it would increase the traffic throughput buy a much greater amount than they could by spending that money.

Bloody Birmingham

"... active traffic management, already in place on ... motorways to the east and north of Birmingham"

I don't mind ATM so much as the application of the technology. For example: I clearly remember one night driving to Bath from Sheffield via the M42 / M5 at 10pm at night. The roads were clear, there were a handful of cars on the road, and predictably enough the ATM was active with lovely variable speed-limit changes every half a mile or so (60mph, 40mph, 50mph, 30mph ... &c.).

Exactly what the fucking point of that was we almost never found out as someone else who wasn't glued to watching the speed cameras in order to avoid a ticket (i.e. driving properly) nearly shunted us behind and then, having expressed his displeasure in the usual fashion, shot off through the patently inactive speed cameras and into the night.

If and when the traffic agencies can invent a 'You are a fucking stupid driver' camera* then I'll believe this has something to do with road safety. Until then I'm just going to have to consider it another blunt instrument to be wielded without skill by people who are either too thick, or too bored, to change a speed limit from 'on' to 'off' at the end of their shift.

* Maybe they already have - if you're looking at the overhead speed limit you aren't looking at the road. And where are you supposed to be looking when you're driving on a motorway? ...

@AC, "incorrect assumptions"

So incorrect you're not even going to mention them? Right...

Yeah, you drive faster, an accident is going to happen quicker. But you remove the 18-wheel bollards from the equation, and there's a whole lot less to get in the way. Cars are no longer less stable at higher speeds, and accidents are caused by closing speeds rather than speed per se.

For lorries overtaking, the only times I've ever seen a lorry have a valid reason for overtaking, it was when faced with a tractor doing 20mph up the A14. Other than that, they always only overtake due to 1mph differences on their speed limiters, while a couple of miles of traffic queue up behind them.

Hell, really we should have lorries off the road completely. Most car accidents only cause injuries in one car, two at the outside, whereas most lorry accidents cause multiple deaths and close the road for the rest of the day. But since Thatcher/Major/Blair flogged off the railways, it's cheaper to drive a hundred lorries up the M6 than it is to put a hundred containers on the back of a train, and the railways are in such bad shape they couldn't handle the extra load anyway.

@The Big Yin

Bang on the money!

The varible limits are a bloody good idea....like any idea will work perfectly when they are used correctly, but sadly some minister on the board will sell the services to the UK Gov and we'll have the bloody things on every major A-road upwards, with nothing to show but higher taxes. Variables work well when you get a roadworks snarle-up, seems to keep people moving when they have to slow down to 40/50, most of the time. You hit an "old-style" roadworks snarle-up that doesn't have variables and you see the difference. This only has two goals, more taxes and adds to UK Gov's wonderful survellence society reputation. Gordon and his CCTV of Doom, seems to want us to be the Big Brother ( thinking more crap TV show than culture here ) of the world, than actually getting the country back on its feet after the financial battering we took recently.

Ah the school run! I do love the ones who park half up the curb, then let little Johnny get out of the car, roadside, then faff about, roadside, getting the push chair out to walk 20 yards to the school gate, all the while little Johnny and his mates are running around the car, in the faffing road!!! You lazy ****'s, drive and then walk the last quarter mile with 'em! Same with shopping car parks. I always park at the back of car parks and walk to the shops, I can't stand all that faffing about trying to squeeze in the last tiny space at the front. In the time it take you to park at the front, I can throw my car in a big space at the back and be in the shop, before you finally put the handbrake on!

@ac also in the UK

The UK also operates a penalty system based on income which I had the dubious pleasure to enjoy. I did 37 in an empty 30 zone literally nothing around and no obstructions. Anyway I ended up being fined the maximum £1000k limit and then received a 25% discount as the magistrates were shocked themselves. It was the highest fine they dealt with. The chap before me was offered a free driving course. Go figure. Same offence different punishment because I work hard. Time to leave I think.

The nice thing about speed cameras

@ The Silver Fox

The M5 doesn't have ATM, the speeds you see displayed are the same ones they've been using ont he motorways for a decade or so, a guidance (which no one obeys) system mainly.

The only ATM signs that are actually enforcable (when it comes to speed limits at least) are the ones which have a little red circle around them. Oh, and regular signs along the road which says "Variable Speed Limit" on them.

@ Matt Vernon

Not every variable speed limit gantry has a camera on it. You were probably lucky the one you passed under was one of them.

@Graham

No, I said "So wrong in your assumptions it's not even worth mentioning. ", if you are going to quote, please quote correctly.

Well since you asked:

"Simple maths for politicians. Let's say we have one lane, and 50m between cars (which is actually pretty good on a busy motorway). 50m at 70mph equals 1.6s. So over the course of an hour we can put a maximum of 2252 vehicles down that lane if they're doing 70mph. Now let's say we have the same distance between cars and we're driving at 80mph. 50m at 80mph equals 1.4s. So over the course of an hour we can put a maximum of 2574 vehicles down that line. By similar working, we can only do 1930 vehicles at 60mph."

But we don't drive at the same distances at different speeds and decreasing average speed increases flow rate up to a point so that is a faulty assumption on which your case is built.

"So in this example, if we could keep the lorries (typically doing 60mph) out of the way of the cars (typically doing 80mph), we can get a 33% increase in the number of cars going through. That leads to one simple conclusion - ban lorries overtaking, and you'll get better road links."

So many things wrong here. It would be nice if it were so but not all lorries do or can do 60, not all cars do, can do or will do more than 60, so you won't necessarily get a 33% increase. In fact it would probably get worse as all the cars got stuck behind the volvo doing 60 in the outside lanes and the inside line is now completely congested with lorries. Then consider exiting a motorway across a single lane of nose to tail lorries.

"There's another reason too, which is that the biggest cause of accidents is having to rapidly respond to changes in speed of othe traffic," Proof?

"and the biggest cause of these changes of speed is dealing with overtaking lorries." Proof?

"Sure, it's the driver's fault that they can't react, but it's the lorry driver's fault that he's pulling out into a stream of fast-approaching traffic" Bit of a blanket assumption?

"In other words, if you ban lorries overtaking, you'll also reduce your accident rate practically to zero overnight." All the premises of the argument are mistaken, so that conclusion can't be drawn.

"So forget speed cameras. If no lorry is allowed to overtake anyone or anything, ever, then we'll have safer, faster roads." Yes, I am sure that's a really practical answer.

Variable Speed Limits

Driving on the M25 regularly, I have to disagree entirely with the people saying that ATM and variable speed limits work. They don't. It is very marked the sudden change in traffic behaviour as you pass under the A3 and enter the "managed" section of the M25 heading for Heathrow. Free flowing traffic cruising at 80 will slow down and bunch up as everyone stops looking at the road and starts paying attention only to their speedo. The exact opposite is true coming the other way, leave the cameras behind and the traffic moves faster and better.

The speed limits are arbitrarily changed with little or no relation to the traffic conditions. A 40 limit is invariably pointless as the traffic is already stationary. Other limits only slow traffic down for no visible reason, frequently on nearly empty roads that could happily be cruising at normal speed.

I'm aware the theoretical mathematical model that the system is based on supposedly shows that slowing the traffic improves flow but experience shows the model doesn't reflect how a real road with real traffic on it behaves.

The gantries should be used only to inform drivers of conditions ahead. They should be up to date and accurate. Even then drivers should only use them as *additional* information to add to what they can see around and ahead of them. An aid to the independent assessment and decision making process that drivers should be constantly engaged in. If drivers cannot do that and need to be told how fast to drive by a sign then they are not competent to drive, it's really that simple. Get rid of all the incompetent drivers by revoking licenses and you'll go a hell of a long way to cutting congestion and the frequency of incidents. A driving license is a privilege, not a right, and it should be revoked if the required standard of driving is not met. Cause an incident? Revoke the license and force retraining and retesting. Once you've been at fault 3 times, revoke it forever.

Most of the dangerous things I see on the road everyday are perpetrated below the speed limit. Even the Home Office's own figures show that only 8% of incidents are caused by speed. Get traffic cops out on the road to sort the bad driving out, no camera will ever be able to do that. Speed is simply not the issue, bad driving is.